Scientists study the influence of porosity on FDM-printed materials

Scientists from the Lobachevsky Institute of Mathematics and Mechanics have used experimental 4D X-ray computed tomography (XCT) for the first time to study samples printed using the fused deposition modeling (FDM) method.

The analytical dependencies they developed allow to assess the effect of porosity on the mechanical properties of the material with unprecedented accuracy: it is now possible to predict the change in the volume of projected macropores inside the sample and interlayer voids under load, and therefore calculate the rigidity and yield strength of printed products.

To conduct in situ 4D XCT research, an innovative sample loading system was created to monitor the dynamics of porous structures in real time. Compression experiments revealed that under elastic deformations, the pore volume changes first, and under plastic deformations, their shape and orientation. It was especially noticeable that at small deformations the main loss of the elastic modulus is provided by interlayer pores, however, as the plastic deformation increases, they 'close' and no longer affect the further behavior of the material.

The study is of key importance, since it was with the help of the developed tooling that the scientists recorded the presence of interlayer pores in samples created by additive FDM technologies. The most important achievement was not only the observation of this effect, but also its successful inclusion in numerical models, which opens the way to more accurate predictions of the properties of printed structures.

"The publication is an important step in understanding the complex mechanisms of deformation of porous materials. We are confident that our results will find practical application in the creation of more reliable and durable structures, including implantable medical devices," commented Nikita Kharin, research associate of the Laboratory of Shell Mechanics.

Additive technologies have become an integral part of modern engineering, noted Ksenia Spiridonova, junior research associate and head of the Student Design Bureau of the Institute of Mathematics and Mechanics.

"Unlike traditional manufacturing methods, they allow us to form a material with a given heterogeneous internal structure. The level of control described in the article opens up wide opportunities for detailed analysis and optimization of the properties of porous materials," she said.

Orthopedic specialists note that modern porous implants require meticulous control of the size and shape of pores, and manufacturers claim that such structures are increasingly used in the aerospace, automotive and energy industries. New data on how pores behave under load will allow us to design products with increased reliability and durability.

"The developed equipment for 4D X-ray computed tomography demonstrated outstanding results, providing high accuracy in analyzing the dynamics of porous structures under load. This innovative system has proven its reliability and efficiency, opening up new horizons for studying the properties of metamaterials. I am confident that the developments of my colleagues will find application in medicine and industry, contributing to the emergence of more reliable and functional structures," opined Oskar Sachenkov, Head of the Department of Computer Mathematics and Informatics.

More information:
Inter-track porosity and macroporosity insights into mechanical properties of FDM printed samples using in-situ 4D XCT
link.springer.com/article/10.1 … 7/s10999-025-09780-6

Provided by Kazan Federal University